Here's my Sunny Knock Outs, with a Crown Princess Margarita on the left. All unpruned, and you can see they are pretty vigorous! I'll cut them back this week. They are at 6-7' now. They are in a bed that gets no irrigation or fertilization, and they are with some huge grasses. They bloom all summer. They've been growing there for 5 or 6 years, but they reached 4' the first year. I'm in zone 6/7, outside of town, and my plants are exposed to tremendous wind.
Sunsprite died in that bed. Carefree Sunshine is in there, and it is growing well.
I kind of wonder what they would have done had I amended the soil or fertilized!
